Rinse valve for vacuum waste system

ABSTRACT

The apparatus and method of the invention provides for a rinse valve for controlling the flow of rinse fluid to a vacuum waste receptacle. The rinse valve comprises a primary rinse fluid flow path and a poppet assembly intersecting the primary rinse fluid flow path. The rinse valve also comprises a solenoid-driven fluid control device having a solenoid armature movable between an inactive state in which the armature engages the poppet assembly to block flow of the rinse fluid through a poppet channel and an active state in which the solenoid armature is disengaged from the poppet assembly to allow flow of the rinse fluid through the poppet channel to raise the poppet assembly, permitting the flow of the rinse fluid through the primary rinse fluid flow path and out of the valve, the armature being located at all times out of the primary flow path of the rinse fluid.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims the benefit of U.S. Provisional PatentApplication No. 61/102,653, filed Oct. 3, 2008.

FIELD OF THE INVENTION

This invention generally pertains to vacuum waste systems and, moreparticularly, to rinse valves for vacuum waste receptacles such asvacuum toilets.

BACKGROUND OF THE INVENTION

Vacuum waste systems are generally known in the art for use intransportation vehicles such as airlines. Vacuum waste systems typicallycomprise a waste receptacle connected by a vacuum line to a waste tank.When a flush valve connected to the waste receptacle opens, the contentsof the waste receptacle are removed by differential pressure to thewaste tank. Generally, rinse fluid is delivered to the waste receptaclevia nozzles to assist in the ease of waste removal and to clean thewalls of the waste receptacle.

Conventional rinse valves for controlling the flow of aqueous rinsefluid to vacuum waste receptacles are generally known. Rinse valves areactuated when a command is initiated from a user input device such as aflush button. Such rinse valves often use solenoid actuated armaturearrangements to control the flow of rinse fluid to the waste receptacle.

In typical designs for solenoid-actuated rinse valves the solenoidarmature is disposed directly in the main flow path of the rinse fluid.Such prior systems present reliability problems because the substantialwetting of the armature with the rinse fluid combined with the drainingof rinse fluid from adjacent the armature during servicing causes thebuild-up of mineral deposits on the surfaces of the armature and itshousing. The friction produced by this mineral build-up initially tendsto cause higher current draw to the solenoid in order to move thearmature over a deposit-roughened surface. Over time, the mineralbuild-up may become so great that the armature may seize in the open orclosed position. A rinse valve with an armature seized in the closedposition will not provide rinse fluid to a toilet while a rinse valvewith an armature seized in the open position will cause flooding of thelavatory area. In addition, bearing and shearing stresses on thearmature and housing surfaces due to friction from mineral build-upcontribute to galling and flaking of surface plating as well ascontamination from micro-particles. A need therefore exists for animproved rinse valve and method for controlling the flow of rinse fluidto vacuum waste receptacles such as vacuum toilets.

Under certain circumstances a rinse valve may be exposed to very coldtemperatures for a prolonged period of time. If prolonged cold exposureand inactivity occur, and the rinse fluid is not drained or isincompletely drained from the rinse valve, it is not uncommon for frozenrinse fluid to form within the rinse valve. In a conventional rinsevalve, the expansion of the frozen rinse fluid inside of the valve maycrack or otherwise damage the valve. A need therefore exists for animproved rinse valve and method for providing protection against damagecaused by rinse fluid freezing within the rinse valve.

BRIEF SUMMARY OF THE EMBODIMENTS

The invention is generally directed to providing improved efficiency andreliability in controlling the flow of rinse fluid for the operation ofvacuum waste receptacles. The apparatus and method of the inventionachieve this by way of a solenoid-operated valve with its armaturedisposed out of the primary flow path of the rinse fluid. This designdramatically reduces the likelihood that the armature and its housingwill develop surface mineral deposits during use. Since armaturestypically slide in the housing between open and closed positions, theresulting dramatic reduction in mineral roughening of the slidingsurfaces results in significantly less wear stress on the valve and lesscontamination of the valve due to flaking and galling of rubbingsurfaces. This increases the reliability and longevity of the valve andreduces the likelihood of a failure.

The valve design of the present invention relies upon differential fluidpressure in controlling the flow of rinse fluid through the valve. Theuse of differential fluid pressure in the valve design reduces the sizerequired for the solenoid and provides for less current draw duringoperation of the armature than would otherwise be necessary. The valvealso provides the unique teaching of self-venting, self-draining andfreeze protection features in a single rinse valve block having acentral solenoid-operated valve.

The rinse valve of the present invention thus includes a valve blockhaving an inlet for receiving aqueous rinse fluid, primary and asecondary rinse fluid flow paths, and an outlet for providing rinsefluid to a waste receptacle or toilet. An inlet venting assembly isdisposed in the valve block, a solenoid/poppet fixture is provided tocontrol the flow of the rinse fluid in the primary flow path, and avacuum breaker outlet assembly is disposed in the valve block downstreamof the solenoid/poppet fixture.

The present invention includes an inlet venting assembly having a sleevevalve mounted between an expansion chamber and an inlet cavity thatprovides protection against damage due to freezing of rinse fluid insideof the valve. Upward movement of the sleeve valve into the expansionchamber accommodates the expanding volume taken up by any formation offreezing rinse fluid forming in the inlet cavity. This feature providesubstantial protection against damage caused by rinse fluid freezing inthe rinse valve.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-noted and other advantages of the invention will be apparentfrom the description of the invention provided herein with reference tothe attached drawings in which:

FIG. 1 is a perspective view of the outside of a rinse valve inaccordance with the present invention;

FIG. 2 is a cross-sectional view of the valve of FIG. 1, taken alonglines 2-2 of FIG. 1;

FIG. 3 is cross-sectional view of the valve of FIG. 1, taken along lines2-2, showing the inlet venting assembly in the closed position and thearmature of the solenoid/poppet fixture in the closed position;

FIG. 4A is a view of a portion of the valve shown in FIG. 3;

FIG. 4B is an exploded view of a portion of the solenoid/poppet fixtureshown in FIG. 4A;

FIG. 5 is cross-sectional view of the valve of FIG. 1, taken along lines2-2, showing the flow path of the rinse fluid when the armature of thesolenoid/poppet fixture is in the open position and the vacuum breakeroutlet assembly is in the closed position;

FIG. 6 is a cross sectional view of a portion of the valve of FIG. 1,taken along lines 2-2, showing the armature in the open position and thepoppet of the solenoid/poppet fixture in the closed position;

FIG. 7 is a perspective view of the sleeve of the sleeve valves used inthe embodiment of the invention illustrated in FIG. 1; and

FIG. 8 is a cross-sectional view of a portion of the rinse valve of FIG.1, taken along lines 8-8, showing the vacuum breaker outlet assembly ofthe rinse valve.

FIG. 9 is a cross-sectional view of the valve of FIG. 1, correspondingto FIG. 2 in which the inlet venting assembly has moved into theexpansion chamber and the armature of the solenoid/poppet fixture is inthe closed position.

DETAILED DESCRIPTION OF THE INVENTION

The embodiment of the invention described below is not intended to beexhaustive or to limit the invention to the precise structure andoperation disclosed. Rather, the embodiment described below has beenchosen and described to explain the principles of the invention and itsapplication, operation and use in order to best enable others skilled inthe art to follow its teachings.

This invention is generally directed to a valve and method ofcontrolling the flow of rinse fluid to vacuum waste receptacles, such asvacuum toilets and vacuum sinks which form part of a vacuum wastecollection system in an aircraft. Turning now to the figures, the rinsevalve 10 of the present invention includes an inlet venting assembly 12,a solenoid/poppet fixture 14 and a vacuum breaker outlet assembly 16 allmounted in a valve block 17.

As shown in FIG. 2, inlet venting assembly 12 includes an inlet cavity18 into which an inlet fitting 20 is attached by suitable means. Aqueousrinse fluid will enter the rinse valve through a conduit 21 in inletfitting 20, passing through an optional filter screen 22 located withinthe inlet cavity. The filter screen 22, sometimes referred to as a “bugscreen,” is United States Public Health Service compliant. The rinsefluid is preferably potable, although grey water may be used with thisrinse valve if desired. Also, the rinse fluid may contain cleaningchemicals, if desired.

A sleeve valve 24 is mounted between an expansion chamber 27 and asleeve valve cavity 26 that is opposite inlet cavity 18. Sleeve valvecavity 26 is in fluid communication with the inlet cavity 18, as shownfor example in FIG. 2. Sleeve valve 24 comprises a sleeve 25 and asleeve supporting member 28 mounted above the sleeve valve cavity 26.Sleeve 25 is supported within sleeve valve cavity 26 by the supportingsleeve member. Also, supporting sleeve member 28 has a vent opening 30in communication with the atmosphere outside of the rinse valve.

Supporting sleeve member 28 has a cylindrical cavity for slidablyreceiving the sleeve 25. As shown in FIG. 7, sleeve 25 has an uppercylindrical portion 32, a lower cylindrical portion 34, and a partition36 for blocking fluid flow between the cylinders. The peripheral wallsof the cylinders have a plurality of ports 40, 42 extending through thewalls. Also, an annular ledge 37 encircles the partition and extendsoutwardly from the cylindrical portions. An “O” ring 38 is positionedabout the upper cylindrical portion 32 on top of the ledge 37. Although,FIG. 7 illustrates nearly identical sleeves of both the inlet ventingassembly 12 and the vacuum breaker outlet assembly 16, it should benoted that the sleeve 25 of the inlet venting assembly 12 has only one“O” ring 38, whereas the sleeve of the vacuum breaker outlet assembly 16includes two “O” rings 138, 139.

When there is no incoming rinse fluid pressure, sleeve 25 is biased soas to be maintained in the open position illustrated in FIG. 2 by aspring 46. In this position the sleeve valve is open so that air mayflow from vent opening 30 past wall ports 40, 42 to the inlet cavity 18and conduit 21. When the rinse fluid entering inlet cavity 18 exceeds apredetermined threshold value, sleeve 25 will slide up into supportingsleeve member 28, closing the sleeve valve 24 by way of the sealingengagement of “O” ring 38 against the bottom edge 44 of supportingsleeve member 28 thereby closing off access to port 30. Accordingly, therinse fluid passes through inlet cavity 18 into sleeve valve cavity 26.Under normal conditions (non-freezing), the force of the rinse fluid isnot great enough to move the sleeve 25 and the sleeve supporting member28 upwardly against the biasing force provided by the spring 47 on thesleeve supporting member 28.

FIG. 3 illustrates sleeve valve 24 in an upward closed position,permitting rinse fluid to flow into the sleeve valve cavity 26. On itsway to this closed position, the sleeve valve will permit air in thesystem to escape. Finally, it should be noted that sleeve valve 24 maybe replaced by other valve types that function comparably such as afloat valve.

The rinse fluid moving past the closed sleeve valve 24 (FIG. 3) enters afirst channel 204 and flows toward solenoid/poppet fixture 14. As shownin FIG. 2, this fixture includes a solenoid 52 and an armature 60 whichmoves within a pressure tube 54 to control the flow of the rinse fluidthrough the rinse valve in response to activation of the solenoid whenthe toilet is flushed. Solenoid 52 includes solenoid coils 56 disposedwithin a coil housing 58 and encircling the pressure tube. The armature60 is positioned snugly and slideably within the pressure tube formovement upwardly against the bias of a spring 62 in response toactivation of the solenoid coils. In a preferred embodiment, thearmature may include a preferably rubber-type surface 64 at its distalend designed to engage a resilient poppet member 90, which will bedescribed below. Other suitable surfaces may also be provided. As alsoexplained below, because the armature 60 of the solenoid/poppet fixtureis outside of the primary flow path of the rinse fluid, a very smallsolenoid with minimal current draw can operate the assembly. This smallsolenoid controls the substantial flow of rinse fluid past the assemblyand ultimately from rinse valve 10 with minimal contact between thearmature and the rinse fluid.

In a preferred embodiment, the pressure tube 54 may be made of Delrin®AF which contains polytetrafluoroethylene (Teflon®) to eliminate theneed for lubrication between the armature 60 and the interior of thepressure tube 54. The use of Delrin® AF or another lubricious materialor coating contributes to the improved reliability and efficiency ofthis valve because it substantially eliminates galling and flakingcontamination. Additionally, this placement of the armature out of theprimary flow path of the vast majority of the rinse fluid moving throughthe valve block increases the reliability and efficiency of the valvebecause the armature is not subject to the detrimental deposit buildupseen in typical rinse valve designs in which rinse fluid is in contactwith a substantial portion of the armature as the valve is operated.

As shown in FIGS. 4A-B, the solenoid/poppet fixture 14 includes a poppetassembly 70 positioned opposite surface 64 of armature 60 andintersecting the primary flow path 200. Poppet assembly 70 comprises apoppet member 90 on the top, which rests within a cavity 77 within aresilient diaphragm 72. The diaphragm receives a rigid annular retainer100 in an annular recess 79 in its bottom surface. A sealing ring 104 ispositioned on a washer 106, which in turn rests on guide member 82, andabuts the bottom surface 105 of the annular retainer 100. Finally, guidemember 82, which supports the sealing ring, is mounted for longitudinalmovement in a circular cavity 18 in the valve block 17. The diaphragm,annular retainer, sealing ring, washer and guide have correspondingapertures for receiving a stem 92 which extends downwardly from thepoppet member 90. The combination of the poppet member 90, diaphragm 72,retainer 100, sealing ring 104, washer 106 and guide 82 is held togetherby the mating of threads (not shown) inside of the guide aperture 86with threads (not shown) on the stem 92.

Poppet member 90 has a circular platform 91 and a centrally locatedaperture 93. The platform also has a raised annular inner seat 94 and araised outer lip 95 encircling a central clearance area 96 in theplatform. Poppet member 90 also includes a longitudinal bore extendingfrom aperture 93 through stem 92 defining a poppet channel 98. In apreferred embodiment, poppet member 90 is made of an engineered polymer,although the invention is not limited to the use of this material.

Diaphragm 72 is made of a resilient material. Material such as NBR/PolyFabric or any other suitable resilient material may be used. Thediaphragm includes a central aperture 74, a raised open ring portion 76,and a rim 78. The rim 78 has an annular recess 79 in its underside. In apreferred embodiment the diaphragm includes at least one pilot channelaperture 80 (as explained later) and includes at least one rim aperture81 to aid in positioning and retaining the diaphragm in the block.

Retainer 100 has a central aperture 102 and an annular upstanding wall103. Upstanding wall 103 is configured to nest within the annular cavity79 in the underside of the diaphragm. The retainer 100 may be made of arigid material.

Sealing ring 104 may be made from a resilient material. Such resilientmaterial may include any rubber-type material. The sealing ring has acentral aperture 107.

Finally, the assembly includes guide 82 having a top surface 84, and abottom surface 85 which rests within a cavity 18 in the valve block 17.A guide aperture 86 is formed in the guide and extends the length of theguide. The guide is configured to move longitudinally within cavity 18of the valve block. In the illustrated preferred embodiment, the guidehas four arms 88 extending radially outwardly from the guide aperture 86along the length of the guide. These arms 88 define passageways 83 inthe cavity 18 for the rinse fluid to flow past the guide 82.

As illustrated in FIG. 2, vacuum breaker outlet assembly 16 includes asleeve valve 124 mounted in a sleeve valve cavity 126 adjacent to asecond channel 208 leading from the poppet assembly 70. The sleeve valve124 comprises a sleeve 125 and a sleeve supporting member 128. Sleeve125 is supported within sleeve valve cavity 126 by a supporting sleevemember 128 mounted above the sleeve valve cavity. Supporting sleevevalve member 128 has a vent opening 130 in communication with theatmosphere outside of the rinse valve. Sleeve valve cavity 126 is influid communication with the vent 130, as shown, for example in FIG. 2.

Supporting sleeve member 128 has a cylindrical cavity for slidablyreceiving the sleeve 125. As can best be seen in FIG. 7, sleeve 125 hasan upper cylindrical portion 132, a lower cylindrical portion 134, and apartition 136 for blocking fluid flow between the cylinders. Theperipheral walls of the cylinders have a plurality of ports 140, 142extending through the walls. Also, an annular ledge 137 encircles thepartition and extends outwardly from the cylindrical portions. An “O”ring 138 is positioned about the upper cylindrical portion 132 on top ofthe ledge 137 and an “O” ring 139 is positioned about the lowercylindrical portion 134 below the ledge 137.

When there is no incoming rinse fluid pressure, sleeve 125 is biased byspring 146 in the position illustrated in FIG. 3. In this position thesleeve valve is open so that air may flow from vent opening 130 pastwall port 142 to the sleeve valve cavity 126. As shown in FIG. 5, whenthe rinse fluid pressure in second channel 208 exceeds a predeterminedthreshold value, sleeve 125 will slide up into supporting sleeve member128 against the bias of spring 146, closing the sleeve valve 124 by wayof the sealing engagement of “O” ring 138 against the bottom edge 144 ofsupporting sleeve member 128 so that the rinse fluid passes through thesleeve valve cavity 126 to the toilet bowl. Finally, it should be notedthat sleeve valve 124 may be replaced by other valve types that functioncomparably such as a float valve.

Valve block 17 includes a primary rinse fluid flow path 200 (FIG. 5) anda secondary rinse fluid flow path 300 (FIG. 3). The primary flow path200 extends from the inlet fitting 20 to the outlet 212 (FIG. 8) leadingto the toilet and is the flow path over which the vast majority of therinse fluid will flow through the rinse valve to the toilet. The primaryflow path 200 passes through conduit 21 defined by inlet fitting 20, afirst channel 204, main chamber 110, guide passageways 83, a secondchannel 208 and a third channel 210 (FIG. 8) which flows through to theoutlet 212.

As illustrated by FIG. 5, the first channel 204 is formed in the valveblock 17 and extends from the inlet fitting 20 to the main chamber 110.The guide passageways 83 are defined by the guide arms 88 and the cavity18 in valve block 17 and extend the length of the guide 82. The secondchannel 208 is formed in the valve block 17 and extends from the end ofthe guide passageway 83 to the vacuum breaker outlet assembly 16. Thethird channel 210 is formed in the valve block 17 and extends throughthe lower cylindrical portion 134 of the sleeve 125 of the vacuumbreaker outlet assembly 16 to the outlet 212 (FIG. 8).

Turning now to FIG. 3, the secondary flow path 300 moves through a pilotchannel 302 to pilot chamber 108. The pilot channel 302 branches off ofthe first channel 204 providing a narrow flow path from the firstchannel 204, through the pilot channel aperture 80 in the diaphragm, tothe pilot chamber 108.

In operation, initially the sleeve valve 24 of the inlet ventingassembly 12 is in the position illustrated in FIG. 2. Ambient airentering the vent 30 is in fluid communication via the sleeve valve 24with conduit 21 of inlet fitting 20. When rinse fluid first enters theinlet cavity 18, the pressure of the oncoming rinse fluid against thepartition 36 (FIG. 7) causes the sleeve 25 to slide up into thesupporting sleeve member 28 thereby moving the sleeve valve 24 to theclosed position seen in FIG. 3. “O” ring 38 is pushed against the bottomedge 44 of the supporting sleeve member 28 sealing the sleeve valvecavity 26 from receiving ambient air and allowing rinse fluid to fillthe sleeve valve cavity 26.

As seen in FIG. 3, the rinse fluid also flows through the first channel204 filling the main chamber 110 and flowing into the secondary flowpath 300 filling the pilot chamber 108. The rinse valve remains in thisinactive state with the main chamber and the pilot chamber substantiallyfilled and the sleeve valve 24 closed until a user flushes the toilet orthe rinse valve is drained during servicing.

As shown in FIG. 4, when the rinse valve is in the inactive state thearmature 60 engages the raised inner seat 94 of the poppet member 90 ina closed position. The spring 62 (FIG. 2) urges the armature against theinner seat 94. The dimensions and shape of the inner seat 94 (FIG. 4)provide a small sealing surface for the armature 60 and thus result in ahigher applied sealing pressure and more efficient seal than if thesealing surface had instead been the entire surface of the poppet 90.When the armature 60 is in the closed position shown in FIG. 4, rinsefluid in the pilot chamber 108 is blocked by the armature from drainingthrough the poppet channel 98.

The rinse fluid in pilot chamber 108 exerts downward pressure againstthe poppet member 90. The central clearance area 96 is dimensioned to bea larger surface area than the bottom surface of the retainer 100against which rinse fluid in the main chamber 110 exerts an upwardpressure. Because of the larger area of the central clearance area 96,the rinse fluid in the pilot chamber 108 exerts a greater downward forceon the upper surface of the poppet assembly 70 than the upward forceexerted on the backside of the poppet assembly 70 by the rinse fluid inthe main chamber 110. This downward pressure helps to keep the poppetassembly 70 in the closed position so that less force is required by thearmature spring 62 (FIG. 2) to hold the poppet assembly closed with thesealing ring 104 engaged against the valve block 17.

When a user actuates the flush switch, a signal is sent to the solenoid52 (FIG. 6). The solenoid is energized in response to the signal and thearmature 60 is drawn upward overcoming the force of the spring 62 andmoving upwardly in the pressure tube 54 away from the entrance to thepoppet channel 98 as shown in FIG. 6. Rinse fluid present in the pilotchamber 108 drains through the poppet channel 98 to the second channel208 (FIG. 6) thereby reducing the fluid pressure exerted on the upperside of the poppet assembly 70. The force exerted by the rinse fluid onthe backside of the poppet assembly 70 is now greater than the forceexerted on the upper side of poppet assembly 70 thus enabling the forceon the backside to move the poppet assembly 70 upward to the openposition illustrated in FIG. 5. When the poppet assembly 70 movesupward, the sealing ring 104 is lifted off of the valve block 17 and theguide 82 is moved upward so that rinse fluid from the first channel 204and the main chamber 110 flows into the guide passageway 83 to thesecond channel 208. From there, rinse fluid flows to the vacuum breakeroutlet assembly 16.

When the pressure exerted by the entering rinse fluid on the partition136 of vacuum breaker outlet assembly 16 exceeds a predeterminedthreshold value, sleeve 125 will slide up into supporting sleeve member128, closing the sleeve valve 124 by way of the sealing engagement of“O” ring 138 against the bottom 144 of supporting sleeve member 128 andpermitting the rinse fluid to pass from the second channel 208 throughthe sleeve valve cavity 126 and third channel 210 to the outlet 212 (asillustrated in FIGS. 5 and 8) where appropriate piping is provided totransport the rinse fluid to the toilet. As long as the armature 60remains open, the rinse fluid flows along the primary flow path 200.

As can be seen in FIG. 5, the armature 60 is disposed out of the primaryflow path 200 of the rinse fluid. As noted earlier, typical priordesigns dispose armatures directly in the primary flow path of the rinsefluid; the passage of rinse fluid combined with draining of the armatureduring servicing creates surface mineral deposit build-up on thearmature and the internal surfaces of the housing surrounding thearmature. Over time this build-up causes the armature to malfunction,first, by slowing the movement of the armature and, ultimately, bycausing the armature to become seized in an open or closed position. Arinse valve with an armature seized in the closed position will notprovide rinse fluid to a waste receptacle, and an armature seized in anopen position will cause flooding of the waste receptacle. Locating thearmature out of the primary flow path dramatically reduces thelikelihood that the armature and its housing will develop detrimentalsurface mineral deposits; this design increases the reliability andlongevity of the valve.

An armature stop 61 comprising a metal conical shell 63 encircling aflat, elastomer or rubber-type pad 65 is positioned at the top of thepressure tube 54. The metal conical shell 63 creates a stronger magneticforce on the armature for a given amount of current than would otherwisebe present. When the solenoid is energized when a flush signal isapplied, the armature moves to the open position seating against the pad65. When a flush signal is no longer received by the solenoid, thesolenoid is no longer actuated and the armature 60 slides downwardlyaided by the force of the spring 62. Use of the rubber-type pad 65 inthe armature stop 61 provides a rebound effect that ensures that thearmature will not remain in the open position due to residual magnetismpresent in the armature stop 61.

The downward moving armature 60 pushes the poppet assembly 70 downwardto a point where the flow of rinse fluid through the guide passageways83 is reduced and rinse fluid begins flowing again to the secondary flowpath 300. However, because the armature 60 is covering the opening tothe poppet channel 98, rinse fluid cannot enter the poppet channel 98.This blockage causes the rinse fluid to build up in the pilot chamber108 and results in pressure from the rinse fluid in the pilot chamber108 being exerted on the upper surface of the poppet assembly 70. Thispressure on the upper surface builds up until it exerts a greaterdownward force on the poppet assembly 70 than the upward force exertedon the backside of the poppet assembly 70 by the rinse fluid in the mainchamber 110. This force differential assists in moving the poppetassembly further downward into the closed position illustrated in FIG. 3with the sealing ring 104 engaged against the valve block 17. Rinsefluid stops flowing to the second channel 208 and to the vacuum breakeroutlet assembly 16.

Once rinse fluid stops flowing to the vacuum breaker outlet assembly 16(FIG. 4), rinse fluid pressure no longer holds the sleeve valve 124closed and the sleeve 125 slides downward until the “O” ring 139 engagesand seals against the valve block 17. The flow of rinse fluid is shutoff to the outlet 212 and fluid communication of air between the vent130 and the outlet 212 is re-established through the sleeve valve 124.In the event of a blockage severe enough to cause waste receptacle fluidto rise to the waste receptacle nozzles and flow backward into thevacuum breaker outlet assembly 16, the backward flow of the wastereceptacle fluid may fill the sleeve valve cavity 126 but will not beable to enter the rinse valve through the vacuum breaker outlet assembly16 because the downward pressure exerted by the contaminated fluid onthe sleeve 125 will keep the sleeve 125 down and sealed by the “O” ring139 thereby stopping contaminated fluid from flowing through the valve10 and into the potable or gray water system.

While rinse fluid is not drained from the valve 10 after each time theactuator is actuated (after each flush by a user), it may be drainedwhen the plane is serviced. During draining of the valve, the flow ofrinse fluid into the inlet fitting 20 is stopped and rinse fluid drainsout of the valve 10. The armature 60 is closed during such draining.

As the rinse fluid drains out of the valve 10, the pressure on thepartition 36 of the inlet venting assembly 12 is reduced and the sleeve25 slides downward to the position illustrated in FIG. 2 where thesleeve 25 is supported by the spring 46. Ambient air from the vent 30 isin fluid communication with inlet fitting 20 through the sleeve valve24. This venting prevents a vacuum from forming in the valve 10 whilethe rinse fluid drains.

The present invention includes design features that provide protectionagainst damage caused by the freezing of rinse fluid inside of thevalve. As illustrated in FIG. 9, the sleeve valve 24 is mounted betweenthe expansion chamber 27 and the sleeve valve cavity 26. A spring 47 ispositioned between the sleeve supporting member 28 and the rim 29 of theexpansion chamber 27. In the inactive state before flushing or draining(FIG. 3), the sleeve valve 24 is disposed in an upward closed positionwith rinse fluid present in the sleeve valve cavity 26, the firstchannel 204, the main chamber 110, the secondary flow path 300 and thepilot chamber 108. If the aqueous rinse fluid freezes, it will expandand exert force on the internal cavities of the rinse valve.

FIG. 9 illustrates the rinse valve 10 when the force of the expandingrinse fluid has pushed the sleeve 25 and the sleeve supporting member 28upwards against the force of the spring 47 into the expansion chamber27. This upward movement of the sleeve 25 and the sleeve supportingmember 28 accommodates the expanding area required by the freezing fluidby decreasing the size of the expansion chamber and, thus, increasingthe volume available in the sleeve valve cavity 26. The features of theinlet venting assembly 12 described above provide substantial protectionagainst damage caused by rinse fluid freezing in the rinse valve 10.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. Recitation of ranges of values herein are merely intended toserve as a shorthand method of referring individually to each separatevalue falling within the range, unless otherwise indicated herein, andeach separate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g., “such as”) provided herein, isintended merely to better illuminate the invention and does not pose alimitation on the scope of the invention unless otherwise claimed. Nolanguage in the specification should be construed as indicating anynon-claimed element as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention. Itshould be understood that the illustrated embodiments are exemplaryonly, and should not be taken as limiting the scope of the invention.

1. A rinse valve for controlling the flow of rinse fluid to a vacuumwaste receptacle comprising: a primary rinse fluid flow path; a poppetassembly intersecting the primary rinse fluid flow path, the assemblyincluding a poppet channel for facilitating opening of the poppetassembly to permit the flow of rinse fluid through the primary rinsefluid flow path; and a solenoid-driven fluid control device having asolenoid armature movable between an inactive state in which thearmature engages the poppet assembly to block flow of the rinse fluidthrough the poppet channel and an active state in which the solenoidarmature is disengaged from the poppet assembly to allow rinse fluidentering the poppet channel to raise the poppet assembly, permitting theflow of the rinse fluid through the primary rinse fluid flow path andout of the valve, the armature being located at all times out of theprimary rinse fluid flow path.
 2. The rinse valve of claim 1 furthercomprising a secondary rinse fluid flow path branching off of theprimary rinse fluid flow path and leading to the poppet channel.
 3. Therinse valve of claim 1, in which the poppet assembly further comprises apoppet member and a resilient diaphragm, the poppet member beingdisposed within a cavity of the diaphragm.
 4. The rinse valve of claim3, wherein the poppet member has a raised inner seat engaged by thearmature in the inactive state.
 5. The rinse valve of claim 1, in whichthe fluid control device further comprises a pressure tube surroundingthe armature and having a spring positioned in a top end of the tube,wherein when the fluid control device moves into the active state thearmature slides in the tube against the force of the spring.
 6. A rinsevalve for controlling the flow of rinse fluid to a vacuum wastereceptacle comprising: a valve block containing a venting assembly, asolenoid-driven fluid control device, and a vacuum breaker outletassembly; and a channel in the block for conducting rinse fluid to theventing assembly, from the venting assembly to the solenoid-driven fluidcontrol device, from the solenoid-driven fluid control device to avacuum breaker outlet assembly, and from the vacuum breaker outletassembly to the waste receptacle.
 7. The rinse valve of claim 6 furthercomprising a screen positioned in the channel between the ventingassembly and the fluid control device.
 8. The rinse valve of claim 6,wherein the inlet venting assembly includes a first sleeve valve and thevacuum breaker outlet assembly includes a second sleeve valve.
 9. Therinse valve of claim 8, wherein the first sleeve valve includes a firstsleeve and a first sleeve supporting member, the first sleeve supportingmember slidably receiving the first sleeve, the first supporting sleevemember having a vent opening in communication with the atmosphereoutside of the rinse valve.
 10. The rinse valve of claim 9, wherein thefirst sleeve has an upper portion, a lower portion and a partition forblocking fluid flow between the upper and lower portions of the firstsleeve.
 11. The rinse valve of claim 10, wherein the upper and lowerportions of the first sleeve each include a peripheral wall havingopenings extending through the wall.
 12. The rinse valve of claim 9,wherein the first sleeve valve is biased open after the rinse valve isdrained allowing ambient air to flow from the vent to the channel. 13.The rinse valve of claim 9, wherein the second sleeve valve includes asecond sleeve and a second sleeve supporting member, the second sleevesupporting member slidably receiving the second sleeve, the secondsupporting sleeve member having a vent opening in communication with theatmosphere outside of the rinse valve.
 14. A rinse valve for controllingthe flow of rinse fluid to a vacuum waste receptacle comprising: aninlet for receiving rinse fluid, the inlet connected to a ventingassembly for venting any air that enters the inlet, the venting assemblyincluding a sleeve valve mounted between an expansion chamber and afirst cavity, the sleeve valve adapted to increase the volume of thefirst cavity by moving into the expansion chamber when rinse fluid inthe first cavity freezes and expands; an outlet for supplying rinsefluid from the valve to the waste receptacle; and a fluid control deviceadapted to selectively establish fluid communication between the inletand the outlet.
 15. The rinse valve of claim 14, wherein air in therinse valve is permitted to escape as the sleeve valve moves into theclosed position and interrupts the fluid communication of air betweenthe first cavity and the atmosphere outside of the rinse valve.
 16. Therinse valve of claim 14, wherein the sleeve valve in the closed positionpermits rinse fluid to accumulate in the first cavity, the force of theaccumulated rinse fluid maintaining the sleeve valve in the closedposition.
 17. The rinse valve of claim 14 further comprising a primaryrinse fluid flow path between the inlet and the outlet and a secondaryrinse fluid flow path branching off of the primary rinse fluid flow pathand leading to the fluid control device, wherein the fluid controldevice includes a solenoid-driven armature movable between an inactivestate and an active state, when the armature is in the inactive staterinse fluid is blocked from flowing through the primary rinse fluid flowpath and when the armature is in the active state rinse fluid flowsthrough the primary rinse fluid flow path, the armature being located atall times out of the primary rinse fluid flow path.
 18. The rinse valveof claim 17 further comprising a poppet assembly intersecting theprimary rinse fluid flow path, the armature in the inactive stateengaging the poppet assembly.
 19. The rinse valve of claim 14 furthercomprising a spring disposed in the expansion chamber around a portionof the sleeve valve, wherein when the rinse fluid in the first cavityfreezes and expands the sleeve valve moves against the force exerted bythe spring.
 20. The rinse valve of claim 19, wherein the sleeve valvecomprises a first sleeve and a first sleeve supporting member, the firstsleeve supporting member slidably receiving the first sleeve.